Staying upbeat is a key to surviving Sea Trials, a 14-hour test of strength, endurance and will that marks the end of the freshman, or "plebe," year at the Naval Academy.

Under the guidance of older midshipmen, plebes beat each other with padded sticks, crawled through muddy trenches under barbed wire, searched for a faux hostage at a water treatment plant and lifted logs as thick as telephone poles over their heads again and again.

They did a run wearing Kevlar vests, rucksacks and helmets; the Marine Corps-style obstacle course; and tests treading water in a pool. In between those stations were push-ups, sit-ups, lunges, squats, crunches and calisthenics.

To civilians, it looked like a day of torture. But to many plebes, the Sea Trials are enjoyable.

"It's all stuff we can do," said Midshipman Will Rose, an aerospace engineering major from Beaver Dam, Va. "It's just mentally preparing yourself. It definitely tests you."

"It's actually fun," said Midshipman Kyle Packer, a math major from Connecticut. After the ruck run in heavy gear, Packer was looking forward to a "wet and sandy" station that involved calisthenics on the shore of the Severn River, alternating with trench crawls.

"It feels great," Packer said.

Midshipman Andrew Lewaniak, a political science major from Illinois, said his favorite was the obstacle course, which involved balancing on giant logs, scaling over logs and finishing with a rope climb.

"I've been looking forward to this all year," Lewaniak said.

Sea Trials, first held at the Naval Academy in 1998, are modeled after the Marine Corps' Crucible and the Navy's Battle Stations recruit training exercises.

This year's version featured less "sea" than in past years. With cool air and water temperatures, it wasn't safe to have plebes trudging through the water for much of the day, said Midshipman 1st Class Victoria Cannon, a senior who led the entire operation as Sea Trials commander.

At a station called "riverine," the plebes were supposed to wade waist-deep in a creek in the woods in search of a pilot supposedly captured by terrorists. Instead, they skipped the creek and just went through the woods.

The relentless push of test after test took its toll on the plebes, many of whom were exhausted before the day was half over. Asked how the day was going, Midshipman Tayler Davidson of Colorado answered simply: "It's going."

"I don't even want to know what time it is," she added.

After finishing the 14-hour day, the top-performing company was honored and plebes were given anchor pins that they'll soon wear to mark that they are no longer plebes. But Midshipman Rachel Busiek, a mechanical engineering major and rugby player from Missouri, didn't expect to have much energy to celebrate.